But when they eventually begin touching Stevie, the scenes are truly outrageous.

The young American woman's vagina is compared to everything from a "furry Star Trek alien" to a "closet door with some curtains poking out."

One man says: “It’s like a partially deflated balloon,” before enquiring: "Can you keep snacks down here?”

And then comes the real challenge.

The gay men are tasked with locating Stevie's clitoris - and it's every bit as awkward as you would expect it to be.

Experiment: One of the men reaches in to touch Stevie's vagina (Image: YouTube)

Filmed by YouTube filmmakers Bria and Chrissy - a singing duo - the video has gone viral, clocking up 3.4 million views since it was uploaded on Sunday.

It comes after another of their videos - featuring lesbians touching a penis for the first time - also went viral.

They say they use music and humour to entertain, share and promote equality.

Explaining why they made the latest video, the pair said: "Men are allowed more sexual freedom than women.

"In our society, when a man has sex he's 'the man' a woman has sex she's a slut.

"We expected a lot of backlash for this video, it will be interesting to see if this video gets the same attention as the 'lesbians touch penis' video since there are female genitals (and a topic about females as a whole) instead of a male genitals."

Apprehensive: The men were visibly nervous before touching Stevie's private parts (Image: YouTube)

But it appears they needn't have worried.

Stevie said she "loved" taking part in the experiment.

Writing under the clip, she said: "I am so so so honored to be a part of this video."

And viewers have praised the footage, commenting on its educational and thought-provoking qualities as well as its humour.

Crystal Chavez said: "I love how this was a very intimate, yet learning experience.

"Its refreshing to see the human body being openly learned about instead of shunned.﻿"